Fe(CO)4PR3complexes have been studied for R = H, Me, Ph, OMe, F, i-Pr, and NC4H4using density functional methods. The Fe-PR3bond has been analyzed in terms of steric and electronic effects. The results obtained show that the main contribution to the bond stems always from the σ donation, but phosphines can be classified into three groups depending on the relative magnitude of the π-back-donation contribution. Thus, PMe3, PPh3, and P(i-Pr)3can be considered as σ-donor ligands, PF3and P(NC4H4)3would be σ-donor/π-acceptor ligands, and PH3and P(OMe)3would correspond to intermediate cases.
|Publication status||Published - 9 Dec 1997|